[hotfix] Fixing the bug related to ipv6 support

Co-authored-by: ByteDance <tongping.liu@bytedance.com>

colossalai/context/parallel_context.py

@@ -370,7 +370,7 @@ class ParallelContext(metaclass=SingletonMeta):
            port (str): the master port for distributed training
         """
         # initialize the default process group
-        init_method = f'tcp://{host}:{port}'
+        init_method = f'tcp://[{host}]:{port}'
         dist.init_process_group(rank=rank, world_size=world_size, backend=backend, init_method=init_method)
 
         # None will give the default global process group for pytorch dist operations